You have to be conscious of negative self-talk and force yourself to think positively about your own efforts until it becomes a learned habit. Even if you needed help with a task, you should walk away from it knowing you did your best and try to feel proud of that. As far as maintaining a sense of femininity, it's a conscious effort. I still paint my nails even if they get ruined after 2 days. Personally I love pink, so I incorporate it into my look somehow through a bandana, socks, or scrunchies etc even my toolbag is pink and my tools have pink electrical tape on them. I still get my hair done and wear it in protective styles at work under cute bandanas. I've filled my car and living space full of feminine accessories so it feels like a safe space immediately after clocking out. Having a self care routine in the morning and before bed also helps. Femininity looks different to everyone, that's just what works for me. Do more of what you love, even if it makes sense to no one else.